Experimental research on the microcosmic mechanism of magnetic memory testing

The microcosmic mechanism of magnetic memory testing showed that in the earth magnetic field,the magnetic domain structure of the loaded-ferromagnetic specimens has directional and irreversible reorientation.The indirectional silicon steel sheets without magnetization and with different bending angles and the different loading 20# steels were made into metallographic specimens.The magnetic domain structure of the specimens has been observed with the Bitter method.The results have shown that under no stress or with small concentrated stress,most of the domains are lamellar before loading,with the load enhancing,the labyrinth domains are appearing and the number of the labyrinth domains increases.The domain walls' length and space changed simultaneously.